I'm loading some swf files at 0 on my stage. They are the pages of my site.
To change from page to page I use removeChildAt(0) and then I addChildAt("page_title", 0).
The problem is that removeChild dont delete the functions from the first swf file loaded (before unloaded).
How can I stop then?
Do I have to use other way to removeChild?
Thanx!
It sounds to me like you aren't actually removing them. First things first, removing something from the display list is only a visual/interactive change. It is still running until you remove any references to it, being event listeners or w/e, and then you must set it to null so that garbage collection will grab it on the next cycle.
If you are using Flash Player 10, spender is correct that unloadAndStop will work for you as they just recently created it to fix your very problem.
I just thought I should explain what is going on, because people should not only know about the fix, but why things happen.
One other suggestion, I wouldn't load these movies to stage, I would create a container Sprite/MovieClip to hold them, that way even if you add other things later, they are separated, clean, and easy to access through their parent (imageContainer_mc for instance).
Assuming you are loading with a Loader you can use the unloadAndStop method.
More info here:
http://www.gskinner.com/blog/archives/2008/07/additional_info.html
Alternatively, you can load the submovie into a different ApplicationDomain to insulate the loaded code from your main app. Take a look at the flash.system.ApplicationDomain class (it's a parameter to the Loader.load() method).
Related
I need to create a single SWF with no external files, so I'm trying to add an internal preloader to my Flash project which has [embed] assets. I know [embed] causes problems with preloaders because it puts the assets on frame 1. I have tried the solutions recommended in these posts, where you set the document class to your preloader class:
Preloader for SWF with embed bytearray
How to create Preloader in AS3
I can get it to work, but ONLY if I comment out any lines of code that involve the stage, otherwise I get an "Error #1009: Cannot access a property or method of a null object reference." Those lines are essential though, so does anyone know how to fix those errors with the stage?
You haven't posted your code or your fla, so all I can do is share what works for me.
First, I wouldn't use Embed. Instead, use a swc. I have found that Embed can be unreliable as far as actually getting the entire asset in there (at least when publishing with Flash Builder + Flash Pro, which is my workflow).
Once you have your assets in a swc, try the following steps:
Set your export frame to Frame 10 (or any frame other than 1--I like frame 10 because then you can read the label that says "Preloader")
Put your actual content on frame 11. You can structure this a lot of ways. Since I program to Interfaces, I give whatever is on frame 11 an instance name and then use a setter to determine that my "first thing" has been placed on stage. I can get away with this because my main Document Class just knows the definition of the Interface, not the full implementation of the Class, so the Class does not need to load for the main Document Class to work. You probably aren't truly using the timeline and probably didn't program to interfaces, so you'll probably just set the base class of the symbol that's on frame 11 to the main logic of whatever you're trying to do.
Put your preloader graphics in Frame 1. I'm not sure why your stage references are so important. I, personally, don't use any logic in the preloader. Instead, I use a spinner that spans frames 1-10 (plus the word "Loading...". The spinner just spins while the classes load. The embed frame acts as a temporary "stop" that just holds the timeline back until those classes have been loaded. Once the classes have been loaded, the timeline will act like you called play() on it. So it really can be that simple. If you need it to be more complicated, give one of your preloader graphics an instance name and set up a getter/setter pair for it, then use the setter to trigger your logic that accesses the stage. You are pretty much guaranteed to have a valid stage at that point.
Word of warning: if you did make use of the timelime, you will get strange results if you try to jump to a frame that isn't loaded yet, so make sure to check to see if a given frame is loaded if it's near the end of your main timeline and your main timeline is heavy with assets before calling goToAndPlay() or goToAndStop().
Some references that might help you further:
Preloaders vs as 3 (I'd recommend you read the entire series this is part of. This is an amazing series I wish I'd found 3 years ago)
Solving the Frame 2 Problem Presentation and code
Combining the Timeline with OOP The example code for that is here (long story)
I have a simple expandable advertisement which loads an external SWF file. The external SWF file contains an embedded video.
Using the UILoader component, I have loaded the SWF, added it to the stage and the video displays and plays fine.
The main issue is that I have a close button, which should unload the video, and stop it, essentially returning to the default state of the advertisement.
To unload the SWF, I am doing the following:
myUILoader.unload();
removeChild(myUILoader);
When I do this, the video and UILoader disappear from the screen. However, you can still hear the sound in the background, and if I load the SWF again, it creates multiple tracks in the background. Any suggestions?
There are a couple of things that could cause this. One is that the content inside your UILoader is adding event listeners to outside of itself. You can fix this by not allowing it to touch anything outside itself. I believe you can do this by placing it either in its own ApplicationDomain, SecurityDomain, or both. Consult the help for more details.
If this is not feasible, you can try SoundMixer.stopAll(), which will stop the obvious symptom, but will not fix the memory leak you probably have in this situation.
Another possibility, as Ronnie has alluded to, is that you still have a reference to the content of the loader somewhere. If you don't clear that, it will stay in memory.
However, there is another problem that can also cause this, which is that if there is navigation in the movie that skips over a frame that contains a MovieClip with audio set to "stream," the MC will be created but not fully instantiated and will stay in memory with no way to get any control over it or release it. I don't think this is what is happening from your description. If it is, the fix is to make sure that you visit the frame that contains the sound, however briefly, on the way to the other frame. This is actually something you might want to consider even without sounds, because it does occur any time you skip frames in nested MovieClips (you just have no evidence unless you profile the swf), and over time this will create a memory leak.
I know the AS3 Loader's class unloadAndStop() supposes to unload and stop everything on a SWF's stage when I load one, but does it also changes objects within the library (even if they are not on stage?).
I'll describe my problem to clear it up: I am loading SWFs dynamically into my AS3 application and extract required symbols from them using applicationDomain and getDefinition. The stage of the SWF/FLA I am loading is empty, and all I have are exported symbols in my library.
The problem happens when I load symbols which have pre-compiled clips inside of them (in my case, a Partigen emitter, but I don't think it really matters), which probably has event listeners or timers - the code on these clips stops working and acts weird when unloadAndStop() is called by the Loader which loaded the clip's parent SWF. I assumed unloadAndStop() removes a required event listener from it, but not sure why (again, it's not on the stage).
I'd write my own kind of unloadAndStop() that filters these pre-compiled clips or checks what's truly going on there, but I am pretty sure that unloadAndStop() does things which are unavailable through the API.
What can explain this behavior? Anyone can think of a possible solution?
Thank you.
Make your loader in this way:
myLoader.contentLoaderInfo.addEventListener( Event.INIT , myLoaderHandler, false, 0, true);
It solves some problems due to unloadAndStop().
I am using the frames in the timeline of a .swf as pages in a flash app. The user can advance to the next page by clicking a button that takes her to the next frame. Similarly, it is possible to navigate to the previous frame/page as well.
Most of the content is placed on the stage (i.e. created by dragging an instance of a library symbol to the stage) but properties of those instances, such as .visible might be changed via actionscript. Also, some objects are loaded from external flash files and displayed programmatically with addChild / addChildAt.
The problem is, if I am on Frame N+1 and there is an object displayed on the stage programmatically (i.e. with addChild, not by having it placed on the stage) and navigate to Frame N where there is an object that is placed on the stage (i.e. dragged from the library),
then the instance of that object is undefined/null and throws an error if I try to set its properties (like .visible).
The error does not occur if I am moving to the NEXT frame, only if I am moving to the PREVIOUS one. Therefore I assume that some kind of initialization is not getting called while going one frame back.
I was also thinking that the objects would just not "live" to the next timeframe, that is, their value would be lost and re-initialized because of scope, but if there is no dynamically created object on the stage, I can navigate back and forth just fine.
Is there a way to ensure that the objects created on the stage do not disappear while navigating back to the previous frame?
The first, and more useful, part of the answer is this: timeline keyframes and scripts can give conflicting information about display objects - whether they should exist, where they should be, and so on. For example, when you add an item by playing into its frame, and then delete it with script, and then play into its frame again. When this happens, there's no unambiguously correct thing for Flash to do, so it tends to be unpredictable. I believe what generally happens is that once you fiddle with a given object via script, it's considered to no longer pay attention to the timeline - but your mileage will vary.
Having said that, the reason things are different when you play backwards is the second and more arcane part of the answer. Internally Flash functions differently when seeking forward and backwards on the timeline. Flash internally treats keyframes as changes to be applied in the forward direction, so as you play forward, it applies those changes in sequence. When you move backwards, however, from frame N+X to frame N, it doesn't scan through the intervening X frames reversing those changes - it jumps back to frame 1 and fast-forwards along to frame N. Normally, it amounts to the same thing and you don't need to worry about it, but when you get into the twitchy area where scripts and the timeline have a different idea of what should be on the stage, you're liable to see things behave differently depending on which way you jump (as you are now).
The super-short version is, for things to work predictably, try to ensure that any given object gets added, updated, and removed the same way - either all via script, or all via the timeline. When that seems impossible, fiddle with your content structure - usually, the best solution is to change your object into two nested ones, so that the things you want to do with script occur one level higher or lower than the things you want to do with the timeline.
I'm not sure I got your question right, but as3 does not instantiate elements on the timeline as soon as you gotoAndSomething, but later that frame.
That is, you can't
this.gotoAndPlay(10)
this.elementOnTimelineFrame10.DoSomething()
without errors.
I remember using this chunk of code in the past to work around this problem. It uses the Stage.Invalidate() function to wait for an Event.RENDER before trying to access and children, more info (although vague as hell) is here
private function init():void
{
stage.addEventListener(Event.RENDER, stage_renderHandler);
}
private function stage_renderHandler(evt:Event):void
{
// Run your code here
updateChildren();
}
private function enterFrameHandler(evt:Event):void
{
// triggers the RENDER event
stage.invalidate();
}
This also might me very costly (performance wise). I would strongly advise against dynamically adding/removing objects to an existing timeline, is there any way in which you can place an empty Sprite above the timeline animation and use that for all your dynamic content?
Hope this helps
How can I create a preloader which does this? I have seen many examples of code to load an external swf, but never something that loads itself.
Thanks for the help, this is driving me crazy...
It's really simple. First you need to move everything except the preloader off the first frame.
Everything else is basically the same as an external preloader - the only difference is that you're checking the current and total size of the current movie, rather than a separate one.
alternatively ...
You can try FlashDevelop's Preloader template, makes it really easy